Metal 3D printing technology has always been one of the most notable areas in manufacturing. However, the presence of support structures has long been one of the significant factors limiting the application scope of this technology.

The addition of appropriate support structures ensures the stability of printed parts to some extent, especially in preventing deformation from thermal stresses, facilitating heat transfer away from the melted material, and shielding the forming part from the recoater blade, which could potentially disrupt the part’s shape upon impact. Moreover, they aid/assist in attaching the part during the build process to maintain stability. However, due to technological limitations, most metal printers limit the angle of unsupported overhanging features (i.e., the angle between the feature surface and the horizontal plane) to approximately 35-45 degrees, necessitating the removal of lower-angle overhangs through a often laborious Post-Processing .

As each additional support structure prolongs printing time and increases material costs, productivity inadvertently decreases. Therefore, it is imperative to find a solution to mitigate the residual thermal stresses produced during multi-layer printing, which may cause low-angle structures to warp upwards. Moreover, the removal of support structures necessitates extra time and labor, frequently leading to defects and deformation or damage to thin-walled structural components. Additionally, adding support to partially enclosed internal structures or tiny internal flow channel structures complicates removal, thereby further constraining the application scope of metal 3D printing technology.

Compared to traditional  printing methods, unsupported/less supported structure printing technology can streamline the production process, enhance production efficiency, and lower costs. However, realizing unsupported/less supported structure printing necessitates several technological advancements, including optimization algorithms for support structures, real-time control of melt pool temperature, optimization of powder deposition, and the development of metal alloy materials tailored for unsupported printing.

HBD recently achieved remarkable results in a turbine blade printing project. We successfully decreased the unsupported angle from the conventional 45° to 6°, leading to a 96% reduction in overall support volume. Throughout the turbine blade printing process, we eliminated the internal support structures of the specimenimpeller, employing only a minimal amount of support structures designed for easy removal. This substantially alleviated the challenges associated with support structure removal and significantly reduced the time required for the process.

Reduce support volume by 96%

Support angle decreased from 45° to 6°

Turbine blade printed by HBD 350 Metal AM System

While achieving 100% unsupported printing remains a challenge, key industry players have initiated research into unsupported/less supported printing technology. HBD is committed to further exploring unsupported/less supported printing technology, aiming to pioneer early technological breakthroughs. Our objective is to provide clients with more efficient and reliable metal 3D printing solutions, thereby expanding possibilities for industrial manufacturing.